Method for the formation of a planarizing coating film on substrate surface

Abstract

A method is disclosed for the formation of a planarizing coating film on the surface of a substrate having a stepped level difference under processing for the manufacture of semiconductor devices. The inventive method capable of giving a planarizing coating film of excellent planarity and good adhesion to the substrate surface comprises the steps of: (a) coating the substrate surface with a coating solution containing, as a film-forming solute uniformly dissolved in an ,organic solvent, a nitrogen-containing organic compound such as benzoguanamine and melamine having, in a molecule, at least two amino and/or imino groups each substituted for the nitrogen-bonded hydrogen atom by a hydroxyalkyl group or an alkoxyalkyl group to form a coating layer; (b) drying the coating layer by evaporating the organic solvent to form a dried coating layer; and (c) subjecting the dried coating layer to a baking treatment at a temperature in the range from 150 to 250° C.

What is claimed is:  
     
       1. A method for the formation of a planarizing coating film on a substrate surface which comprises the steps of: 
       (a) coating the substrate surface with a coating solution consisting of an organic solvent and, as a film-forming solute uniformly dissolved in the organic solvent, a nitrogen-containing organic compound selected from the group consisting of melamine, benzoguanamine, acetoguanamine, glycoluril, urea, thiourea, guanidine, dicyandiamide, alkylene ureas and succinamide having, in a molecule, at least two amino or imino groups each substituted for the nitrogen-bonded hydrogen atom by a hydroxyalkyl group or an alkoxyalkyl group to form a coating layer;  
       (b) drying the coating layer by evaporating the organic solvent to form a dried coating layer; and  
       (c) subjecting the dried coating layer to a baking treatment at a temperature in the range from 150 to 250° C.  
     
     
       2. The method for the formation of a planarizing coating film on a substrate surface as claimed in claim  1  in which the alkyl group of the hydroxyalkyl group and alkoxyalkyl group substituting the nitrogen-containing organic compound has 1 to 4 carbon atoms. 
     
     
       3. The method for the formation of a planarizing coating film on a substrate surface as claimed in claim  1  in which the alkoxy group of the alkoxyalkyl group substituting the nitrogen-containing organic compound has 1 to 4 carbon atoms. 
     
     
       4. The method for the formation of a planarizing coating film on a substrate surface as claimed in claim  1  in which the film-forming solute in the coating solution is a methoxymethylated benzoguanamine or a methoxymethylated melamine. 
     
     
       5. The method for the formation of a planarizing coating film on a substrate surface as claimed in claim  1  in which the organic solvent of the coating solution is selected from the group consisting of alkyleneglycol monoalkyl ethers and esters thereof. 
     
     
       6. The method for the formation of a planarizing coating film on a substrate surface as claimed in claim  1  in which the baking treatment in step (c) is conducted for a length of time in the range from 1 to 30 minutes.